Evaluating blue spectral irradiance, illuminance level and the associations with health and wellbeing in older adults

This paper reports seasonal difference in light exposures and health and wellbeing indicators as well as predictors of sleep quality parameters in care home dwelling older adults. The quality of lighting in the indoor environment can impact upon the health and wellbeing of building occupants. For older adults in care homes poor light exposure has been attributed to disruptions in the sleep/wake cycles. The repeat measure design explored personal illuminance and blue spectral irradiance exposure and sleep/wake patterns in older adults in two seasons (n=16). The cohort was assessed across a suite of health and wellbeing indicators. Statistical analysis included a paired means test to detect changes over time and an exploratory analysis of predictors of sleep parameters. Light exposures and daytime physical activity were significantly different between seasons (i.e. these were higher in summer). Morning blue light exposure (a predictor of total night-­time sleep), daytime activity level (a predictor of sleep efficiency) and visual function (a predictor of minutes awake during the night) may contribute to sleep quality. This paper presents insights into the limited amount of light exposure in older adults and architectural characteristics that that could serve to promote health and wellbeing.